Now is the best time to see the Summer Milky Way | Astronomy.com – Astronomy Magazine

Posted: July 13, 2023 at 4:56 am

The early-summer Milky Way stretches across the sky above Skull Rock at Joshua Tree National Park. Credit: NPS/Hannah Schwalbe

In the Northern Hemisphere, the Milky Way is at its best in the summer months. During the winter and spring, the parts of the Milky Way that are visible are subdued, sparse affairs, little more than a vague mist of faint stars breathed on the window of the sky, running down through Perseus and Auriga and falling to the left of Orion. But when summer comes, as dust sheets are whipped off barbecue grills and Bermuda shorts are taken out of their hibernation drawers, the Milky Way is one of the star attractions in the sky.

Summer is when the glittering star clouds of Cygnus are at their highest, a haze that hangs overhead in the brief, darkest part of a balmy summer night. Framing them, the stars of the Summer Triangle Deneb, Vega, and Altair blaze through the night like finely cut jewels. And sweeping along the length of the Milky Way with binoculars or a small telescope reveals a bewildering number of knots and froths of stars and a sparkling treasure chest of nebulae and clusters.

Everyone knows that, right?

Kind of.

Frustratingly, for observers living at mid-northern latitudes (like me, writing this in the UK), a lot of the good stuff is so low in our sky that it is hard to see through all the haze and murk there. Celestial objects our southern friends see high in the sky are often hidden behind trees, buildings, and hills on our skyline. Consequently, many mid-northern observers dont even try for famous objects such as the Lagoon and Trifid nebulae, or star clusters such as M4 and M22. And two of the most famous and striking constellations in the sky Sagittarius and Scorpius are hard to see too, for the same reasons. This is why many observers dont even bother trying to look farther down the Milky Way than the star cluster M11 in Scutum: They think its just not worth it.

But theyre wrong.

For mid-northern observers willing to put in a bit of effort, these famous objects, which theyve never seen and maybe havent even tried to see, can be observed, photographed, and enjoyed. You just have to be in or rather, get yourself to the right place at the right time: somewhere with a low, flat southern horizon, late at night during the end of June and through July.

Yes, your targets will be low in the sky and challenging, but rewarding to finally see with your own eyes which is, after all, one of the most fundamental rewards and appeals of amateur astronomy.

To see these elusive summer objects, you need an observing location with the most advantageous view. Perhaps your favorite spot is just fine, but many people might need to find an alternative site. Unless you know your local area well and already have somewhere in mind, this will mean doing some research, either by driving around until you find somewhere suitable or, if thats not possible, spending some time virtually exploring on Google Maps .

Either way youll be looking for somewhere with a flat and low southern horizon, without tall trees, buildings, or hills to block your view of the sky in that direction.

You will need to be properly dark adapted to see these summer showpieces at their best because they are faint and diffuse, so find somewhere with as little light pollution as possible. Any streetlights, security lights, or illuminated advertisements in their direction will wash nebulae and clusters from the sky. Passing traffic is just as much an enemy as static lights, so find somewhere away from the roads, where you wont be dazzled every few minutes by the retina-scorching headlights of a passing car or truck.

Dark adaptation

You might think that dark adaption is not important when it comes to viewing the Milky Way in summer because the sky is so much brighter than the autumn or winter sky. But thats not the case. Even the lightest balmy summer night, when only the brightest stars, planets, and constellations fight through the twilight, is much darker than daylight. So, the Milky Way will definitely stand out more clearly if you take the time to let your eyes adapt to the low light levels. Get as far away from artificial lights as possible and try to avoid looking at your phone, too, as even a brief glimpse at a dimmed screen is bright enough to ruin your dark adaption.

All these objects will be at their best around midnight through July and into early August, but you will need to do just a little more research before setting off on your summer Milky Way safari. Find a night when theres no bright Moon in their part of the sky, which will wash them from view. The best observing windows this year are between July 10th and 24th.

Some of these objects are visible to the naked eye but others need binoculars or a small telescope to see them. Dont worry, well give you all the information you need to best view each one.

Using binoculars

Although the summer Milky Way can look very attractive to the naked eye, it is much better seen through binoculars. In this case, dont worry too much about knowing what youre looking at or about trying to identify everything you see using a star atlas or a planetarium app on your phone. For a while, at least, just be happy to be a sightseer!

Slowly sweep your binoculars down and across the Milky Way and enjoy all the stars that drift through their field of view. In some places theyll be as thick as diamond dust or pollen grains; in others, they will be packed less densely and youll sense the voids between them. Beautiful knots, chains, and streamers of stars will pass before your eyes as you pan down the Milky Way, and occasionally a star cluster or misty nebula will appear too. Take your time. Dont rush. Just enjoy drinking in the view.

Here are 12 celestial objects for you to track down on your summer Milky Way safari. Youll likely recognize the names of many of them and will have seen gorgeous photos, either taken by amateur astronomers like yourself or by the Hubble and James Webb space telescopes, but some will be new to you. That doesnt matter. Just enjoy looking for and finding this delightful dozen and seeing them for yourself.

This 5th-magnitude globular cluster is only 10,000 light-years away, making it one of the closest globular clusters we know of. Almost a hundred light-years across, its half a million stars can be seen with the naked eye as a smudge with the same apparent diameter as the Full Moon. A pair of binoculars show it as a smoky ball, while even a small telescope will be powerful enough to resolve the stars that surround its bright central core.

Of the many globular clusters in Sagittarius, M28 is a popular target. At 18,000 light-years away, this buzzing beehive of stars has a magnitude of 6.8, which means it is too faint to see with the naked eye. But look at it through a telescope and youll be able to see its bright core and fainter surrounding halo.

This huge, distant cloud of glowing gas isnt named after a ferocious carnivorous plant; instead, it gets its name from the way that its brightest section is split into three very distinct areas, or lobes, by dark dust lanes. With a magnitude of 6.3, M8 can be seen easily through binoculars, while a small telescope will reveal tantalizing hints of detail and structure on nights of clear air and good seeing. Larger-aperture instruments really add depth to the nebula, showing it comprises an emission nebula, a reflection nebula, and those dust lanes too. But dont expect to see the famously vibrant reds and cool blues of this 5,200-light-years-distant cloud through your telescope; they only show up on long-exposure photos.

More than 4,000 light-years away and some 100 light-years wide, the Lagoon Nebula is one of the most famous deep-sky objects in the whole sky. With a magnitude around 6, it is visible to the naked eye at the darkest time of the night as a misty patch and is much more obvious in binoculars as an extended nebulous area. But when seen through a telescope, the Lagoon really comes to life and some dedicated deep-sky observers think it is as beautiful as the Orion Nebula (M42). The Lagoon Nebula is split into two unequal sections by a prominent dark dust lane. To one side of the dust lane, youll see a glittering cluster of stars superimposed in front of a pale gas cloud, while to the other, youll see a large area of much brighter misty nebulosity with many fascinating subtle streamers, whirls, and swirls. Although the nebula is a lovely orange-pink color in long-exposure photos, your eye will only see vague hints of those hues and the nebula will appear as a misty grey patch through your eyepiece.

M21 is a loose open cluster, containing only 57 or so stars, spread out across 20 light-years. With a magnitude of about 6, it is technically a naked-eye object, but in reality youll need a pair of binoculars or a small telescope to pick it out from the bright summer sky. The cluster is very young, only 4.6 million years old, and is nearby, too some 3,900 light-years away.

Visually, this globular star cluster is a quite subdued object. At magnitude 7.6, it is well below the threshold of naked-eye visibility and appears as just a fuzzy star in a pair of binoculars. Through a telescope the view doesnt really improve much, with the cluster resembling a smooth, hazy patch without a noticeably bright core. What makes this 300-light-year-wide ball of stars interesting is that it is not actually part of the Milky Way. Measurements show it lies more than 86,000 light-years from us and belongs to the Sagittarius Dwarf Elliptical Galaxy, making it the first extragalactic globular cluster discovered.

The Hubble Space Telescope has taken thousands of images since it launched, but few have captured the imaginations and hearts of astronomers and the public alike like The Pillars Of Creation. A trio of ragged columns of gas and dust surrounded by glittering stars, the famous pillars are actually only one small part of the Eagle Nebula, a 15-light-year-wide cloud of gas and dust that lies 7,000 light-years from our solar system. Youll need a large telescope to see the pillars for yourself because they are so small and faint, but the nebula surrounding them shines with a magnitude of 6, making it a naked-eye object. Although past studies indicated these structures had been blown away a supernova thousands of years ago and the light from their destruction simply hadnt reached us yet, more recent followup with newer instruments shows they are, fortunately, here to stay for tens of thousands of years. However, nearby starlight is evaporating the pillars, and they wont stick around forever.

Observers like myself who live at mid-northern latitudes are jealous of their southern counterparts because we can never see the beautiful Magellanic Clouds, the stunning Omega Centauri cluster, or Alpha Centauri, because they never rise above our horizon. But even worse, the brightest part of the Milky Way, the combined glow of millions of old stars in its center, never climbs very high in our sky. Photos taken from the Southern Hemisphere torture and torment us daily in books and magazines. We stare longingly at its airbrushed froth of yellow suns, cut across by lacy lanes of dark dust, and imagine what it must be like to see it high in the sky. But we only see it either through or just above the tops of trees, dimmed and muddied by the haze and murk that linger near the horizon. And the farther north you live, the less of the center you can see, because the southern horizon cuts it off.

But if you can find somewhere with a clearer view south, perhaps on a south-facing coast looking out to sea or high on a hill looking across open countryside, the core of the Milky Way is a beautiful sight to the naked eye: a glowing, smoky patch of light the size of your outstretched hand, dappled with light and dark. Through binoculars it is a sublime sight, scattered with gemstone stars and nebulae that look like smudges of chalk dust. If you hear a promising weather forecast, try to get to somewhere that will let you see it. It will be worth the trip.

How to photograph the summer Milky Way

Having seen spectacular images of the summer Milky Way in books and magazines and online, youll want to take your own. But the most jaw-dropping of those images werent taken with phones. Although the cameras that now come with smartphones are incredible and can be set to take long exposures, if you want to take detailed portraits of the Milky Way showing its magnificent star clouds and smoky dust lanes, youll need a more advanced camera. This should preferably be a DSLR on a motorized mount that allows you to take long exposures by tracking the stars as they move across the sky. Single long exposures can reveal a lot of detail, but if you really want to capture the magnificence of the Milky Way, youll need to take multiple exposures and layer or stack them together to make a single, ultra-long-exposure image.

One of the most striking objects in the summer Milky Way is a pattern of eight stars known as the Teapot. Its not a constellation but an asterism, a distinctive pattern or shape of stars that forms part of a constellation. The Teapot is part of Sagittarius, just as the Big Dipper is part of Ursa Major and the Sickle is part of Leo. The Teapot is always low in the sky from mid-northern latitudes, but it genuinely does look like an old-fashioned teapot. If youre blessed with clear skies (and a good imagination), you can even picture the Milky Way as steam rising up from its spout.

To the right of the tilted Teapot of Sagittarius is a graceful curve of stars representing a heavenly scorpion. The brightest of these stars is orange-red Antares, the Rival of Mars, an enormous red supergiant star that dwarfs our own Sun and is even larger than mighty Betelgeuse. First-magnitude Antares is the brightest star in that part of the sky but only the 15th brightest star in the sky as a whole. Long-exposure photos show Antares is surrounded by and embedded in a cloud of dust and gas, which is buffeted by the fierce solar winds gusting from the star.

This globular cluster, which can be found just to the right of ruddy Antares, is one of the closest globulars to us, just 7,200 light-years away. It can be seen with the naked eye at a magnitude of 5.6 and looks like a round smudge through binoculars. Seen through a telescope, which can resolve stars around its edges, M4 is a very pretty cluster. Its a favorite with many summer observers, but looking at it I always feel rather cheated: If there wasnt a cloud of dust lying between it and us it would be a much more striking naked-eye sight in our sky and a finer telescopic object.

Much higher in the sky than M4, globular cluster M107 has a magnitude of 7.9, which means youll only see it through binoculars or a telescope. 21,000 light-years away, this loose globular cluster has a diameter of around 80 light-years and contains around 50,000 stars. In comparison, the great Omega Centauri cluster, much farther south in the sky, has a diameter of 150 light-years and contains an estimated 10 million stars.

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Now is the best time to see the Summer Milky Way | Astronomy.com - Astronomy Magazine

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